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Comments 129801 to 129850:

129801. Patrick 027 at 03:16 AM on 3 May 2009
        It's the sun
        ... And importantly, the radiative behaviors of the gases ARE understood.
129802. Wondering Aloud at 06:57 AM on 2 May 2009
        Are sea levels rising?
        I have seen the 2mm/year assumption in a lot of places including in the IPCC report of course there listed as 15-20 cm per century. I agree the 6 to 10 meter claims are rediculous! But maybe you better tell Al Gore. The claim in AIG is 20 feet. I actually don't have a problem believing that 1.5 degree change would eventually cause a 5 meter rise. I don't say it would, some folks claim that would in fact take a 5 degree rise, but I could certainly be convinced by data on that. My problem is with the panic time frame. A change of 5 meters that takes a millenium and simultaneously moves growing seasons North by 300 miles is a heck of a lot less scarry. Then we could talk about what to do about it in real terms.
129803. Patrick 027 at 03:32 AM on 2 May 2009
        It's the sun
        "Those of us in non-theoretical sciences and professions follow the laws of thermodynamics to practical ends and know that they can not be violated. They simply can not be applied to open systems, ie. living things and the earth itself precisely because they are open systems. It's the reason that climate models do not work." 1. Did my textbooks and college and high school courses not benifit from actual experiments as well as mathematical derivations, etc? Being in the field has value. However, if we are not allowed to stand on the shoulders of giants, how would our science and technology (and philosophy, politics, etc.) ever progress? Furthermore, Gord and some others with related arguments are arguing points that can easily be argued against based on rather simple observations from everyday life, basic logic, and just a general understanding of physics; it isn't really necessary to know all the ins and outs of QED to see that Gord's version of the 2nd law required some rather miraculous processes. 2. To say that climate models do not work is innaccurate. They are not perfect but they are good enough for some purposes (probably better than you think). Often in science, technology, and life, there is an important role for useful approximations. 3. It isn't actually necessary to use the second law to analyze the entire system as a whole. That would actually not be so helpful in producing a model. Instead: Use the ideal gas laws and thermodynamics on the small scale. When air changes pressure and then a diabatic heating or cooling occurs, the changes in temperature and density are quite predictable. Some microscopic and small scale processes (momentum, thermal, and mass diffusion and turbulent mixing) - though they can be modelled individually - cannot be modelled explicitly as part of a general circulation model because of limited computing power, but they are understood and can be parameterized. In other words, the underlying physics are understood. The only real limitations are limited computing power, so that the model's grid scale cannot resolve all processes explicitly, so that some processes have to be parameterized, but those processes can be understood. A human is not a closed system; mass goes in and out, energy goes in and out in various forms; yet, we understand fairly well the consequences of eating more or less of at least the macronutrients, excercising, and what happens if you jump in the air (aside from air drag, your center of mass will accelerate downward at approximately 9.8 m/s^2)...
129804. Patrick 027 at 03:10 AM on 2 May 2009
        It's the sun
        Great info, chris! --------- A couple more comments about the second law of thermodynamics: The inability (within bounds of random 'error' of microscopic events - being random, these 'errors' might just contribute to entropy anyway) for a system to spontaneously reduce entropy without increasing entropy elsewhere is a result of the statistics and probability of microscopic processes. It is not a result of some 'physical force' that actually drives heat from a hot object to a cold object in the same way that gravity pulls matter together and electromagnetism describes the interaction of charged particles, etc. -------- Regarding heat transfer by radiation: Radiation is emitted when there are energy transitions between two states available of the kind that will emit radiation (of a particular energy, polarization, direction) and the system (or the relevant portion of it - an electron, a molecule, a crystal lattice) is in the more energetic state. This happens, as I understand it, with some rate of decay - except for stimulated emission (as in a laser), which is dependent on electromagnetic waves passing by, the energy transition between states happens randomly in time, with some probability over any interval of time, so that a population of such energized states will decay exponentially. When a system is in the lower energy state of such a pair of states, there is some probability that radiation of some energy, polarization, and direction, will be absorbed by the system. Other energy transitions can occur without radiation, or with radiation at a different energy, etc, that will put energy into such states so that it can emit radiation, and energy transitions may remove a system from such states without emitting radiation, or emitting radiation at a different energy, etc. The greater the occupancy of some set of states in a system, the greater the rate at which energy transitions will occur to reduce that occupancy. However energy is distributed in a system, a tendency toward thermodynamic equilibrium results in a redistribution of energy until the distribution of energy is such that energy transitions occur at the same frequency as their reverse transitions. What determines blackbody radiation intensity is how much radiant energy there must be for a system at a given temperature to absorb radiant energy at the same rate that it emits radiant energy. The emission of a photon is generally a locally-determined process.
129805. chris at 02:02 AM on 2 May 2009
        Are sea levels rising?
        Re #1 Wondering Aloud, your analysis of sea level changes encompassed in this sentence doesn't accord with the evidence:

        Sea level has been rising for thousands of years and for the last two centuries at about 2 mm per year.

        In fact the evidence indicates that sea levels were pretty steady during at least the two millenia (2000 years) before the 19th century. So sea levels haven't been rising for thousands of years, at all. And of course they've only been rising "for the last two centuries at about 2 mm per year", if one averages over the whole two centuries. In fact if one analyses sea level rise more carefully during this period (see IPCC AR4 pages urled below), they were hardly rising at all during the early part of the 19th century, and only started to accelerate during the early part of the 20th century. See for example the papers cited below [***]. Some of this is summarised in the IPCC AR4 (see chapter 5 pp 408-411, for example): http://www.ipcc.ch/pdf/assessment-report/ar4/wg1/ar4-wg1-chapter5.pdf Your assertion about claims of imminent sea level rises and so on, seems a straw man argument, since no one considers that 6 or 10 metres of sea level rise is imminent! Unfortunately since you seem reluctant to substantiate your assertions with evidence/sources, it's not clear what to make of them. The bottom line is that rather small temperature rises of around another 1 - 1.5 oC of warming will take the Earth's global temperature to a value that is similar to that existing during the last interglacial 125,000 or so years ago when sea levels were around 4-5 metres higher than now. No one considers that such a sea level rise is "imminent". However it would likely be inevitable in a world with the temperatures we are pretty likely to see at the end of the 21st century, such that our descendents would/will have to accommodate themselves to a committed sea level rise of this order. [***] JA Church et al. (2008) Understanding global sea levels: past, present and future Sustainability Science 3, 9-22 K Lambeck et al. (2004) Sea level in Roman time in the Central Mediterranean and implications for recent change. Earth Planet Sci Lett 224:563–575
129806. Wondering Aloud at 00:21 AM on 2 May 2009
        Are sea levels rising?
        Actually I avoid that thread, it is the one where you are least cionvincing. Opposing understated positves vs sometimes silly exaggeration of negatives. For example 5.74% excess deaths due to heat waves vs 1.59% for cold snaps? Both numbers wildly high and the placing of heat waves deaths higher is just laughable. No matter how shoddy the editorial review process at New Scientist wass I can't believe they published that howler. At best it is an example very similar to the deliberate confusion of sea ice and land ice you were complaining about the other day on that thread.
        Response: If you're not convinced of all the positives versus the negatives of global warming, all the more reason to post your comments there where they're relevant rather than on an unrelated topic. For starters, I suggest explaining exactly what problem you have with the methodology of the heat wave/cold snap research published in New Scientist.
129807. Philippe Chantreau at 15:25 PM on 1 May 2009
        How to cherry pick your way to Antarctic land ice gain
        Looking at the data for global sea ice on Cryosphere Today, considering the bottom red line, daily anomaly. How much of the past 2 years has been spent with a positive anomaly? eyeballing, about a month in late 07-early 08 and about 3 to 4 months in 08. That's 5 months out of 24, or 21% of the time. The rest, 79%, was spent in negative anomaly. What is the direction of the largest anomalies? Negative, as we see late 07 and late 08 reaching or flirting with -3. How large have the positive anomalies been? You have to go back to 1987 to find one that exceeds +1.5; 96, 01 and 08 barely exceed +1. It means that the largest recent positive anomaly does not reach 35% of the largest recent negative anomaly. I'll add that, without the short tiny spike in late 06, you would have 3 straight years of negative anomaly. Do you see something different on that graph? This:"Our analysis, using this specific method of data handling and adjustment, from this set of specific data gathered in this specific way seems to suggest" Is not the same as "the science says". Actually, it is exactly the same thing. IMO you were mistaken if you ever perceived science to mean something else. There is no such a thing as certitude.
129808. Wondering Aloud at 06:54 AM on 1 May 2009
        How to cherry pick your way to Antarctic land ice gain
        Well as of yesterday the anomaly was down some, to +675,000 km2. Thats Still mighty positive and as I characterized it is a small negative in the arctic and a large poistive anomaly in the antarctic. The problem I have with this is it doesn't seem to fit my idea that thickening of the ice in the continental interior and fairly high snow fall are caused by warming of the surrounding sea. It isn't definitive and I didn't say it was. I just don't see how someone draws the conclusion that it fits warming either. I don't know what you're looking at either. I think I am looking at same data as cryosphere today data I am getting it originally through U of Illinois linked site similar address. Odd in that my unsupported assertions are coming from your sources. I told you I have colleagues they are having more trouble with thickening that thinning and that is land based. I also told you that I did not think thickening proved anything. As I have told you before on this, though you may not remember, I will not risk an important piece of research becoming a witch hunt target because some fanatic reader fears their data may damage his pet cause. It is not their intent to enter this debate on either side. They just aren't noting the ice getting thinner, they are having some trouble because thickening has been greater than expected. Chris I will investigate your references if I get a bit of time it would be interesting to know. How does it match up with the permafrost studies?
129809. Wondering Aloud at 03:33 AM on 1 May 2009
        Are sea levels rising?
        I agree John I have no problem with this. Sea level has been rising for thousands of years and for the last two centuries at about 2 mm per year. Here it looks like about 3mm per year? I think we all expect sea level to continue to rise. We would need very large net cooling to get us a negative slope wouldn't we? One point though, the actual skeptic argument is that the 6 meter (lately I've seen 10 meters) plus rise that is claimed to be immenent by the alarmists is not supported by the data and the prediction from 5 years ago that a tipping point had been reached and rapid rise was about to start, specifically at 30 times the currently observed rate, is not supported by the data. Hoping for warming.
        Response: Future sea level rise is a subject of a future post - I started a post on sea level rise about a week ago and the topic grew and grew to the point where I've divided it up into several posts. I'm always saying get the complete picture but it's not easy to communicate the complete picture in a single blog post.
        
        As for your last comment, thoroughly read all the positives versus the negatives of global warming and tell me you're still hoping for warming.
129810. Olympus Mons at 03:05 AM on 1 May 2009
        Is the climate warming or cooling?
        [ Response: Here is a good summary of the empirical evidence for positive feedback in the climate system. ] Don't think so. You should update info. Of course looking these up on the web is excruciatingly difficult. Now, finding stuff that takes the AGw stance is by the millions. Most of what is postulate there is old stuff. Very much pre “oh my god, global temps are not increasing anymore”. But, anyway, here goes a couple to help out: http://translate.google.com/translate?js=n&prev=_t&hl=en&ie=UTF-8&u=http%3A%2F%2Fwww.radiobremen.de%2Fwissen%2Fnachrichten%2Fwissenawipolararktis100.html&sl=de&tl=en&history_state0= http://www.abc.net.au/news/stories/2009/04/24/2552225.htm
129811. Olympus Mons at 03:00 AM on 1 May 2009
        Is the climate warming or cooling?
        [ Response: Here is a good summary of the empirical evidence for positive feedback in the climate system. ] Don't think so. You should update info. Of course looking these up on the web is excruciatingly difficult. Now, finding stuff that takes the AGw stance is by the millions. Most of what is postulate there is old stuff. Very much pre “oh my god, global temps are not increasing anymore”. But, anyway, here goes a couple to help out: http://translate.google.com/translate?js=n&prev=_t&hl=en&ie=UTF-8&u=http%3A%2F%2Fwww.radiobremen.de%2Fwissen%2Fnachrichten%2Fwissenawipolararktis100.html&sl=de&tl=en&history_state0= http://www.abc.net.au/news/stories/2009/04/24/2552225.htm
129812. chris at 02:24 AM on 1 May 2009
        How to cherry pick your way to Antarctic land ice gain
        Re #1 WA This doesn't seem right either in the light of the scientific data. Why not cite the sources of your assertions?

        WA: "....but I think most are still finding tha Antarctic land bound ice is not decreasing and that near the pole (the larger portion of the continent) it is increasing in thickness."

        There are continuous analyses of polar (Arctic and Antarctic) land ice, using either the GRACE gravity calculating satellites or satellite altimetry, and these show that Antarctic land ice is decreasing. Some of the most recent data can be found here: Chen JL et al. (2008) Antarctic regional ice loss rates from GRACE Earth and Planetary Science Lett. 266, 140-148 and here: Moore P and King MA (2008) Antarctic ice mass balance estimates from GRACE: Tidal aliasing effects J. Geophys. Res. 113 art # F02005 which show Antarctic polar ice mass loss of around 164 +/- 80 km(3) per year in the period April 2002 - Jan 2006. As John Cook has shown in his top post it's very easy for the unscrupulous to misrepresent the science in this area. So statements like "near the pole (the larger portion of the continent) it is increasing in thickness", are misrepresentations of the important question (of whether Antarctica is in net mass balance or is growing or shrinking) since no one expects that in the high altitude polar interior the ice cap won't increase in thickness somewhat as snow is deposied there. The question is whether melting at the edges of the ice cap (we're not talking about sea ice) is greater than the accumulation of snow/ice in the interior. The science indicates that the net mass balance is negative. It's not a huge amount of mass loss in the grand scheme of things, but no-one expects a very significant mass loss in Antarctica, at least for a while; Greenland melt is a much greater concern. However we may as well address the science rather than base our "understanding" on unsupported assertions!
129813. Olympus Mons at 02:19 AM on 1 May 2009
        Is the climate warming or cooling?
        David Horton, None of those measures would do anything to offset AGW. Absolutely nothing. You can’t answer the question (the Roger Pielke paradigm), can you?
129814. Olympus Mons at 02:17 AM on 1 May 2009
        Is the climate warming or cooling?
        Oh, and btw, the question of "what would have to happen to make me doubt AGW" or what is “inconsistent with AGW theory” is valid for anyone here who believes in it. Because if you don’t know this…
129815. Olympus Mons at 02:01 AM on 1 May 2009
        Is the climate warming or cooling?
        Steve L at 04:57 AM on 29 April 2009 Steve, now I’m the one confused. I’m no expert on the science of global warming, but I’m pretty sure, doubling CO2 on the atmosphere will only be able, per se, to increase temp 1 degree per W/m2. If these were what are at stake here, we would not be here. There would be no issue at all! So this is not the global warming theory. The global warming is about positive feedbacks (as you say climate sensitivity, right). It is about cloud cover, it is about water vapor. It is about behavior on LW and SW radioactive values. So yes, it is all about the positive feedback of cloud cover and what is the behavior of the extra amount of water vapor when that same water vapor organizes itself in precipitation systems. Are those precipitation systems a positive or negative feedback; is cloud cover a fixed value and, since it isn’t, in that form is it a positive or a negative feedback. If you know any scientific study that tries to postulate that those are positive feedbacks, please redirect me to them. Because most scientific paper I’ve been able to grab about this issue, are by any means --- Jokes. I confess that regarding how those feedbacks operate my source is reading Gavin Schmit and Real climate. I know not a reliable source and that is why I'm asking for something more trustworthy. Thank you for your time.
129816. chris at 01:55 AM on 1 May 2009
        How to cherry pick your way to Antarctic land ice gain
        Re #1 WA You make a number of unsupported assertions that don't seem to accord with the scientific evidence:

        The original theory that warming would occur first near the poles and most at night is certainly now refuted as well, unless the time lag is MUCH bigger than thought.

        (i) night/day warming: There has been considerably more warming at night compared to daytime warming. The most recent analysis is: Vose, R.S. et al. (2005) Maximum and minimum temperature trends for the globe: An update through 2004. Geophys. Res. Lett., 32, L23822. and the data can be accessed from the IPCC report (AR4) (see page 244): http://www.ipcc.ch/pdf/assessment-report/ar4/wg1/ar4-wg1-chapter3.pdf During the period 1950 - 2004, night-time (minimum) warming considerably exceeds daytime (maximum) warming. Night-time warming is around 1.15 oC during this time (over land) whereas daytime warming is around 0.75 oC. The details are complicated by other factors. For example the aerosol load has suppressed daytime warming somewhat in the early period of the analysis and the last 15-20 years has seen some cutback of aerosol load over total land surface which has seen daytime temperatures rebound somewhat in the more recent period. But overall night time warming has significantly exceeded daytime warming. (ii) warming at poles: Modelling since the early 1980's predicted that enhanced greenhouse-induced warming would be focussed in the Northern polar regions leaving the Antarctic regions relatively unaffected for considerable periods. For example a recent review of early modelling of the ocean response to global warming described predictions from early modelling: S. Manabe and R. J. Stouffer (2007) Role of Ocean in Global Warming J. Meterolog. Soc. Jpn. 85B 385-403 quoting from this article in the sections describing the predicted hemispheric asymmetry (much greater N. hemispheric polar warming and delayed Southern polar warming): Discussing the early models of Schneider and Thompson (1981) to evaluate the delay in the response of the sea surface temperature to gradual increase in CO2, Manabe and Stouffer say:

        [“Their study shows that the time-dependent response of zonal mean surface temperature differs significantly from its equilibrium response particularly in those latitude belts, where the fraction of ocean-covered area is relatively large. Based upon the study, they conjectured that the response in the Southern Hemisphere should be delayed as compared to that in the Northern Hemisphere because of the inter-hemisphere difference in the fraction of the area covered by the oceans.”]

        In a later model Bryan et al (1988) made the same sort of analysis, investigating the role of the oceans in modulating the response of surface warming to enhanced greenhouse gases.

        [“They found that the increase in surface temperature is very small in the Circumpolar Ocean of the Southern Hemisphere in contrast to high latitudes of the Northern Hemisphere where the increase is relatively large.”]

        It’s not just the oceans per se of course. It’s also ocean and air currents, and particularly the mechanisms governing the efficiency of surface heat transfer into the deeper oceans. If this is efficient, the deep oceans will absorb heat and there might be little measured surface warming, at least for a while. So (speaking of Bryan et al (1988)) again:

        [“However, the detailed analysis of the numerical experiment reveals that the absence of substantial surface warming in the Circumpolar Ocean is attributable not only to the large fraction of the area covered by the oceans but also to the deep penetration of positive temperature anomaly into the oceans.”]

        Later models predict the same hemispherical asymmetry that is seen in the real world. e.g. discussing the simulations of Manabe et al (1992):

        [“Figure 3 also reveals that there is a large asymmetry in surface warming between the two hemispheres. In the Northern Hemisphere, the surface warming increases with increasing latitude, and is particularly large in the Arctic Ocean. This is in sharp contrast to the Southern Hemisphere, where warming is relatively large in low latitudes and decreases with increasing latitudes. It becomes small in the Circumpolar Ocean of the Southern Hemisphere, particularly in the immediate vicinity of Antarctic Continent.”]

        Why is this, one might ask?! Here’s what Manabe and Stouffer say:

        [“One can ask: why the polar amplification of warming does not occur in the Southern Hemisphere, despite the existence of extensive sea ice which has a positive albedo feedback? As discussed in the following section, the absence of significant warming in the Circumpolar Ocean of the Southern hemisphere is attributable mainly to the large thermal inertia of the ocean, which results from very effective mixing between the surface layer and the deeper layers of ocean in this region. This is in sharp contrast to the Arctic Ocean, where very stable layer of halocline prevents mixing between the surface layer and the deeper layer of the ocean.”] [“In view of the absence of significant surface warming, it is not surprising that the area coverage of sea ice hardly changes in the Circumpolar Ocean despite the CO2-doubling.”] (n.b. remember this is a prediction from a model; we’re nowhere near CO2 doubling yet!). However that's what we're seeing in the real world.

        So the delayed warming in the deep Southern oceans and Antarctic is consistent with models/predictions from more than 20 years ago. and so on….
129817. chris at 19:00 PM on 29 April 2009
        It's the sun
        Re #327 Your timings and causes are incorrect Quietman. The collision of the African and Eurasian plates that "squeezed out" the Tethys Ocean and drove the crumpling and nappe formation that raised the Alps occurred 20-ish million years ago. It had nothing to do with the PETM. The PETM was an event of widespread gobal warming and considerable extinctions associated with the massive release of greenhouse gases. It coincides temporally (as Patrick has indicated) with the opening up of the North Atlantic as the plates seperated centered around what is now Iceland, and dated around 55-56 million years ago. Whatever the ultimate cause of the release of the greenhouse gases (both CO2 and methane are implicated) the evidence indicates a very massive (several thousand gigatonnes) release of isotopically-light carbon (i.e. tectonically-derived, or methane hydrates...) into the atmosphere. see for example: M. Storey et al. (2007)Paleocene-Eocene Thermal Maximum and the Opening of the Northeast Atlantic Science 316, 587 - 589 abstract: “The Paleocene-Eocene thermal maximum (PETM) has been attributed to a sudden release of carbon dioxide and/or methane. 40Ar/39Ar age determinations show that the Danish Ash-17 deposit, which overlies the PETM by about 450,000 years in the Atlantic, and the Skraenterne Formation Tuff, representing the end of 1 ± 0.5 million years of massive volcanism in East Greenland, are coeval. The relative age of Danish Ash-17 thus places the PETM onset after the beginning of massive flood basalt volcanism at 56.1 ± 0.4 million years ago but within error of the estimated continental breakup time of 55.5 ± 0.3 million years ago, marked by the eruption of mid-ocean ridge basalt–like flows. These correlations support the view that the PETM was triggered by greenhouse gas release during magma interaction with basin-filling carbon-rich sedimentary rocks proximal to the embryonic plate boundary between Greenland and Europe.”
129818. Philippe Chantreau at 16:51 PM on 29 April 2009
        How to cherry pick your way to Antarctic land ice gain
        WA, We must not be looking at the same graph. The global anomaly (red line bottom part of graph) shows several excursions and even long periods around -2 with troughs down to -3. The periods of positive anomalies are not only fewer and far between but none reaches even +2 in the recent past, which seems to be what you consider. The very way your sentence is worded is strange and could mean many things. Anomaly positive now and for "much" of the past 2 years. How much? Is it more than the time spent in negative anomalies? What is the direction of the largest anomales? How large have the positive anomalies been, compared to the negative ones? I don't really care who your colleagues are but references once again would be helpful. Are you saying that Grace has it wrong? What ice are we talking about? Land based, shelf, sea ice, coastal, continental? I don't know much about the Steig paper except that skeptic blogs seem to have made it a target. I know that this statement of yours: "suggests warming the last 50 years but cooling for the last 30" does not make sense at first glance. O.M.: A reversal of the trend over the next 20 years would not a priori comply with the consensus model. But then again the speed of the recent negative trend is far beyond what the model suggested so it does not comply either.
129819. David Horton at 14:10 PM on 29 April 2009
        Is the climate warming or cooling?
        #15 Well OM: 1. Rapidly phase out coal mines; invest heavily in energy conservation measures and renewable energy sources; end land clearing. 2. Hmm, tricky, but I'm expecting sainthood. You see even if I am wrong (and I dearly wish I was), the measures in the first answer would make this a much better planet for all its inhabitants (human and non-human).
129820. Patrick 027 at 06:17 AM on 29 April 2009
        It's the sun
        If we're talking about PETM - well I don't have all the timings memorized, but the more familiar culprit, so far as I am aware, is rifting between Greenland and the rest of North America.
129821. Steve L at 04:57 AM on 29 April 2009
        Is the climate warming or cooling?
        Dear O.M., Your comments are frustrating to me. You say the theory 'resides on the fact' ... fact A, fact B(1), and fact B(2). You should provide citations that support your assertions that AGW depends on A, B(1), & B(2). If you did that, readers would be able to figure out what you're saying. Of course, doing that would also mean you would have in your possession a good clue as to why those assumptions would be made. AGW does not, however, depend on positive feedbacks -- anthropogenic CO2 provides a positive forcing regardless of water vapour; however the response of water vapour to the CO2 forcing will enhance the climate's sensitivity.
129822. Olympus Mons at 03:28 AM on 29 April 2009
        How to cherry pick your way to Antarctic land ice gain
        Hi Philippe Chantreau, If artic ice keeps on regaining mass and aproaching to median 70-00value will you begin to cast doubt on AGW theory? if not, what would? thank you for your time.
129823. Olympus Mons at 03:20 AM on 29 April 2009
        Is the climate warming or cooling?
        Hi Steve L Can you provide scientific arguments that clouds are a positive feedback on CO2 warming? Because the theory resides on the fact that they are! Can you provide scientific arguments that increase temperature, from CO2 added, will increase precipitation systems and that those systems are a positive feedback? Because the theory resides on the fact that those are a positive feedback. – If they don’t, there is no AGW.
        Response: Here is a good summary of the empirical evidence for positive feedback in the climate system.
129824. Steve L at 00:39 AM on 29 April 2009
        Is the climate warming or cooling?
        W.A. -- could you point me to the late '80's / early 90's paper by Hansen and/or Schneider where they indicate 2-3 C by the year 2000? Regarding disproval of AGW, etc, my understanding is that theories are discarded when others are shown to be better. More usually, modifications are made to an existing theory to improve its predictive power. Interestingly, estimates of climate sensitivity to 2x CO2 have been quite invariant. See: http://tinyurl.com/yzdled (>30 years ago 1.5-4.5 C) http://tinyurl.com/66tphc (4th IPCC note#4 2.0-4.5 C) Those who think AGW is not scientifically supported should provide scientific arguments (especially on a website dedicated to examining those arguments), and they should hopefully use citations to bolster their arguments.
129825. Wondering Aloud at 23:23 PM on 28 April 2009
        Is the climate warming or cooling?
        Lee I was trying to explain that a theory that fails to explain the observations. All observations, not just selected ones, must be discarded. A theory is an explanation it must explain what has been observed and be useful to predict the results of future experiments. What I am trying to get across is that if their is one piece of evidence that contradicts theory the theory is the thing that is wrong. This is not a majority vote, if 99.9% of data support a theory and 0.1% disagree that means the theory is wrong and that's all there is to it. This is the way science works and the politicization of this issue is what is creating the huge backlash. In reality when a theory is well established we look for errors first and then for modifications or a variable we missed. This is where we are right now. It is clear that the hypothesis of AGW by CO2 as popularized by people like James Hansen and Steve Schneider 20 years ago, i.e. 2-3 degrees C net warming by the year 2000, was totally wrong. The theory has to change and is changing. Back off a bit let honest science debate, pretending the science is other than it is harms your cause.
129826. Olympus Mons at 23:07 PM on 28 April 2009
        Is the climate warming or cooling?
        David Horton, 1)What action do you expect out of govements that can have any, any impact on global warming? 2)do you aknowledge that taking action has consequences too. If time disproves AGW, what should the penalties be to people like you? thank you.
129827. Olympus Mons at 22:09 PM on 28 April 2009
        Is the climate warming or cooling?
        David Horton, 1)What action do you expect out of govements that can have any, any impact on global warming? 2)do you aknowledge that taking action has consequences too. If time disproves AGW, what should the penalties be to people like you? thank you.
129828. Olympus Mons at 21:58 PM on 28 April 2009
        Is the climate warming or cooling?
        Gary, that’s what is becoming known as the Roger Pielke Take: what needs to happen to invalidate the AGW theory (or what is inconsistent with the AGW theory as he has put it). When Pielke posed that question, it became clear that… short from an Iceberg in New York, nothing! And that has a reason. AGW is a political movement. And juvenile reasoning has it that political movements are related to truth or reality. They do not! From the point that AGW has become a political movement it will not be invalidated. Some might argue, no way, if facts become clear, there is no way it can not happen. Truth is, it’s a political movement… Global warming became Climate change and currently is becoming, just to be on the safe side, climate change and energy conservationism! – See, whatever results from the coming years, the “climate change” can even be dropped that the “energy conservationism” stay on, and what ever are the objectives of the political movement subsist. – That’s how our species survive. Just face it.
129829. Gary at 18:18 PM on 28 April 2009
        Is the climate warming or cooling?
        1998 to 2009 is the longest post industrial flat/cooling trend. I'm curious, how long of a period without temperature increase would it take (without a Volcanoe, etc) with continued C02 increase before you would accept it as evidence against C02 as a significant cause of warming? Also, how low would temps need to go before accepting it as evidence against AGW?
129830. Wondering Aloud at 07:36 AM on 28 April 2009
        How to cherry pick your way to Antarctic land ice gain
        Re Steig(2009) http://www.climateaudit.org/?cat=140 This may be denialist in your book, and I suppose it is as it allows anyone to join in and unlike RC does not immediately delete any intelligent descent. But if you think Steig is significant you better read up on it here or you will be surprised later on. My first response on reading Steig was that the method looked shaky and the trend was dependant on the dates chosen and a mighty weird way of filling in missing spots that tended very strongly to amplify what was happening in some of the worst stations in one small area and using it to represent a much larger area. You are always going to run the risk of this when the data is limited. I know that my colleagues are having a lot more trouble with thickening ice than thinning but that may be bias because thickening means more work. However they do not agree with the premise that the land bound ice is shrinking. I agree that increasing ice thickness at the pole may not mean cooling, in fact I would think that may indicate warming in the surrounding sea. It took me a long time to look up the global ice anomaly links and than when I hit submit I get an error message and it's all gone. But, you can find it at cryospere and various places including NSIDC it is at about +850,000 square km this week due to the antarctic being at about +1 million and the arctic being very near normal. I don't know what you want, the data, including the data you refer to shows global ice anomaly positive and has for much of the last 2 years. So the land bound ice may be thickening and the sea ice is above normal, and the Steig paper though flawed suggests warming the last 50 years but cooling for the last 30. Where am I supposed to get sudden dramatic warming from this?
129831. Quietman at 07:17 AM on 28 April 2009
        It's the sun
        Patrick Don't you think that the collision of Africa into Eurasia might have had a little to do with that? (That IS when it happened you know)
129832. Patrick 027 at 03:04 AM on 28 April 2009
        It's the sun
        Well, I can't really argue with you so much about the PT extinction except to say that the role of the Siberian traps' CO2 emissions over a million(s?) years(even if caused by an impact) might be expected to be significant. "Nothing to do with CO2 or temperatures. The PETM was roughly 55 million years ago, we evolved from primitive primates to prosimians in Asia, this was a benefit to our own ancestors." PETM seems to have been caused either by a large CO2 release, a large CH4 release (that would eventually oxidize to CO2), or maybe both. It might have been triggered by volcanism but may have involved destabilization of CH4 hydrates, rather than being direct geological emissions of CO2. There was a temperature increase. It was not a mass extinction on the scale of KT or PT, but there was at least some ecological disruption (I just don't know the magnitude offhand as suggested by the evidence). Sure, we may owe our existence to it. We also owe our existence to KT and PT mass extinctions. We don't need to replicate those things to continue our existence. "And of course their is the constantly evolving bacteria. The largest part of the biomass by far in the air, on the surface and below it, in the water and in the muck below it, all do well in warm conditions." In terms of biomass, they might have some competition from krill (?). They certainly do evolve, but the plethora of metabolic pathways (photosynthesis types..., fermentation, respiration, methanogens and methanotrophs, sulfate reduction...) has not changed much for a long time.
129833. Lee Grable at 17:49 PM on 27 April 2009
        Is the climate warming or cooling?
        Wondering Aloud, if you're trying to disprove my arguement,you can't use as the basis for your arguement evidence that I'm using in my arguement ,to disprove my arguement, unless you have further evidence , which, combined with my evidence which you chose to use can be used to disprove my arguement. You've yet to provide that further evidence.
129834. Lee Grable at 17:38 PM on 27 April 2009
        Is the climate warming or cooling?
        Well,part of exposing the erroneous science is understanding the tactics used by the skeptics to keep the illusion of a debate alive. Like trying to start an arguement about whether plants need CO-2 to live. I've seen lots of people get sucked into that one. A prime example on this site is the 'tectonic plate' arguement. A more intelligent arguement to be sure, but still a manufactured arguement, and pointless to the discussion. And you clearly don't understand those tactics. which puts you at a disatvantage when it comes to communicating with the Average Joe. Or the average Lee. Like me.
129835. Patrick 027 at 14:27 PM on 27 April 2009
        It's the sun
        ... Elaborating on what I was explaining, the second law of thermodynamics is a description of what may and may not be reversable. A necessary condition for reversability is that entropy is conserved - thus, a reversable process is an isentropic process, - examples include adiabatic processes (sound familiar? isentropes, potential temperature, etc.), wherein there are no heat flows across system boundaries... An increase in entropy cannot be reversed. Notice how different this is from some more fundamental physics. Consider the conservation of momentum and energy, reaction and reation: if a billiard ball hits another billiard ball in an elastic collision (so that none of the macroscopic energy is transferred to random molecular motions, etc.), however they bounce, one can take positions at time t after the collisions, and from that point, if the spins and velocities are precisely reversed, the collision runs in reverse, producing the exact reverses of spins and velocities, backwards along the same trajectories, as had initially occured before the collision. This is part of a general pattern in physics - in gravity (an orbit works backwards and forwards), electromagnetism, etc. Irreversability occurs because the chances of producing the precise setup for reversal as in the above example can be quite small, and for a system with many components, an arrangement of components that is identifiable as special (lower entropy) from the macroscopic scale is less likely to occur if the arrangement is chosen at random. Higher entropy states are states wherein a larger subset of possible arrangements (states differentiable on the microscopic scale - precise positions of each individual component) will produce the same macroscopic state, so that there is a greater chance of achieving such a macroscopic state. Hence, random processes on the microscopic level tend to increase entropy, and this is irreversable because of the low probability of the system finding a 1 in a million arrangement that is noticeability 'special' (low entropy) on the macroscopic scale.
129836. Quietman at 12:11 PM on 27 April 2009
        It's the sun
        Re: "(PETM, end-Permian mass extinction (?) )." Nothing to do with CO2 or temperatures. The PETM was roughly 55 million years ago, we evolved from primitive primates to prosimians in Asia, this was a benefit to our own ancestors. The PT extinction was an ocean impactor near Antarctica destroying nearly 90% of marine species. Like the KT impact we had the creation of traps on the opposite of the impact (Deccan Traps), in this case the Siberian Traps. The subsequent terrestrial extinction was not quite as bad at roughly 70% of species. There is good reason to suspect the Bedout crater but this is as large an argument as the KT extinction. I could go on but this is not the right thread for it, I think "Climate Changed Before" would be more appropriate. But don't let me interfere with your discussion with Gord. In the mean time I'll go through my notes and find some references for you (to post in the other thread as mentioned).
129837. Quietman at 11:58 AM on 27 April 2009
        It's the sun
        Yes both the summary and the details only concern the relationship of CO2 to Temperature under all the known variables so much information isn't there. I say it's for the layman as none of the infoermation was anything that I was not already aware of and commonly available for anyone interested. I just happen to be interested. Some of the facts covered have been known since the late 1800s, some are as recent as about 20 years. "Your proposed mechanism doesn't seem likely. The amount of biomass today is comparable to the amount in the atmosphere and is less than in the soil. A decrease in biomass means that there is C that is not in biomass - where did it go? The soil, the atmosphere, the upper ocean, and/or the deep ocean? Simply having more biomass does not increase the atmospheric CO2 by breathing; biologically-driven changes in C levels are determined by imbalances between photosynthesis and respiration/oxydation and by where these things occur." Obviously I disagree. The KT extinction killed off ALL large fauna and destroyed a good portion of the flora as well. So we had a situation where O2 and CO2 were high and the new species developed in an O2 rich atmosphere whereas the dinosaurs had been born into an O2 poor atmosphere and plants that did not get the full benefit of CO2. ie. new types of plants took over and with them new types of fauna (not that the genera were new but now they increased in diversity and population). Mammals use much more O2 and consequently produce more CO2 as byproduct. The warmer it gets the wider the range and the larger the populations. Grass was relativly new and naturally followed by grass eaters which causes more methane as that is the nature of grazing animals. And of course their is the constantly evolving bacteria. The largest part of the biomass by far in the air, on the surface and below it, in the water and in the muck below it, all do well in warm conditions. Then of course there is plate tectonics and the consequences thereof on ocean currents and climate. In short, there are multiple causes for CO2 following temperature and they all point to life itself.
129838. Patrick 027 at 11:36 AM on 27 April 2009
        It's the sun
        "Are you starting to see my issue with chris here? This is exactly what I tried to point out earlier. Those of us in non-theoretical sciences and professions follow the laws of thermodynamics to practical ends and know that they can not be violated. They simply can not be applied to open systems, ie. living things and the earth itself precisely because they are open systems. It's the reason that climate models do not work." No. I may have made some terminological slip ups (enthalpy vs internal energy vs thermal energy vs heat), but by and large, on the points where disagreement occurs, I AM right, Gord IS wrong - and just try to find a physics or engineering department that disagrees.
129839. Patrick 027 at 11:34 AM on 27 April 2009
        It's the sun
        "There are no major extinctions caused by increased CO2. This is quite clear in the fossil record so it is not harmful to the planet. " Illogical conclusion (it depends on how much, how fast, and define 'harmful to the planet' (to what degree, in what way)), and the basis may not be correct (PETM, end-Permian mass extinction (?) ).
129840. Patrick 027 at 11:31 AM on 27 April 2009
        It's the sun
        Re Quietman - "Chapter 6 is essentially written for the layman, not much actual information, just speculation:" ... sounds like the summary. It goes further and discusses evidence and theory. "Overall the statements made in the entire PDF are based on the GHG hypothesis being factual as presented by Hansen. IF you accept his hypothesis"... I don't remember offhand if it mentions continental drift and geologic outgassing changes, but ... it might; there is mention of the PETM. Anyway, most climatologists are well aware that there are other factors that work alongside CO2 and also work through and from CO2, and the IPCC is not trying to state otherwise. There is certainly discussion of Milankovitch cycles and - I don't remember for sure if it appears in chapter 6, but internal variability is definitely discussed within the IPCC AR4 WGI. Furthermore, remember that climate theory holds that CO2 and other greenhouse gases affect climate via LW radiative forcing. Climate theory is not that CO2 is the only important factor in all climate changes for all time. Application to the present situation strongly suggests that we should expect that anthropogenically-forced changes in atmospheric CO2,CH4,etc. levels will have a significant warming effect, and the natural forcing changes that have occured in the comparable time periods have been small by comparison; what has yet to be demonstrated or shown as a strong contender is that the climate is much much more sensitive to solar TSI, solar UV, or much much much more sensitive to solar wind and geomagnetic effects or tidal forcings, then it is to other forcings in general, and in the absence of robust evidence and/or theoretical foundations, it is hard to give much credence to the ideat that more than a relatively small bit of recent changes are due to such forcings. In contrast, theory and evidence together and each in isolation make a case for the sensitivity of climate to Milankovitch cycles when near or within some threshold range, as well as for the more general 3 +/- 1 deg C per 4 W/m2 tropopause level radiative forcing sensitivity for many other forcings such as from CO2. "What it actually indicates is that CO2 follows temperature and is powerless to stop natural cooliing." The robust correlation of CO2 to temperature merely shows that there is a relation; the actual causal links must be elicidated by combining paleoclimatic data with laboratory data (radiative properties, ideal gas laws, momentum conservation, dishpan experiments of general circulation, isotopic studies) and computer models based on physics and data. "By not looking at WHY CO2 follows temperature they make a grave error and that makes the recommendations misleading. Temperature increases allow increased biomass, both flora and fauna. In warmer climate the increased biomass creates the increased CO2 by simply breathing." They actually do look at why CO2 follows temperature but there are significant uncertainties remaining. What has been established is that it is very likely that in the ice ages, relative to interglacials, C is removed from the atmosphere, biomass, also maybe soils, and the upper mixed layer of the ocean (lower temperature increases the equilibrium CO2 concentration in water for a given concentration in air, but not enough to have CO2 concentration in the surface water stay the same or increase when the atmospheric decrease was so large), and given the slowness of the geological branches of the C cycle, the deep ocean is the best candidate for where the C went. Your proposed mechanism doesn't seem likely. The amount of biomass today is comparable to the amount in the atmosphere and is less than in the soil. A decrease in biomass means that there is C that is not in biomass - where did it go? The soil, the atmosphere, the upper ocean, and/or the deep ocean? Simply having more biomass does not increase the atmospheric CO2 by breathing; biologically-driven changes in C levels are determined by imbalances between photosynthesis and respiration/oxydation and by where these things occur.
129841. Patrick 027 at 08:55 AM on 27 April 2009
        It's the sun
        More on the role of chemical weathering: http://www.scitizen.com/screens/blogPage/viewBlog/sw_viewBlog.php?idTheme=13&idContribution=286
129842. Mizimi at 06:55 AM on 27 April 2009
        Water vapor is the most powerful greenhouse gas
        Chris G: Think cycles. The earth rotates so it goes through a heating/cooling cycle. WV taken up during the day will precipitate out at night if it contacts a surface cool enough....dew. Obviously if the temp drops sufficiently the general air mass will reach saturation point ( dewpoint). At sunrise, this saturated air is warmed and the dewpoint rises so the air is no longer saturated and can take up more WV. Whether the mass of air ever reaches saturation point during the day depends on how much water is available to evaporate and also that there is sufficient energy to evaporate it. The Saharan atmosphere is dry because although it has enough heat it doesn't have the water. Tropical forests can almost saturate the local atmosphere as both heat and water are present in sufficient quantities to allow this.
129843. Mizimi at 06:41 AM on 27 April 2009
        Do cosmic rays cause clouds?
        Here is the website of the Danish Technical University giving outline details of an experiment carried out to determine if and how cosmic rays might affect cloud formation. The results surprised them.
129844. Quietman at 04:01 AM on 27 April 2009
        It's the sun
        Chapter 6 is essentially written for the layman, not much actual information, just speculation: [It is very likely that glacial-interglacial CO2 variations have strongly amplifi ed climate variations, but it is unlikely that CO2 variations have triggered the end of glacial periods. Antarctic temperature started to rise several centuries before atmospheric CO2 during past glacial terminations.] - page 435 [It is likely that earlier periods with higher than present atmospheric CO2 concentrations were warmer than present. This is the case both for climate states over millions of years (e.g., in the Pliocene, about 5 to 3 Ma) and for warm events lasting a few hundred thousand years (i.e., the Palaeocene-Eocene Thermal Maximum, 55 Ma). In each of these two cases, warming was likely strongly amplified at high northern latitudes relative to lower latitudes.] - ibid. "Antarctic temperature started to rise several centuries before atmospheric CO2 during past glacial terminations." from the first paragraph is accurate, the rest pure assumption based on Hansen's hypothesis. Overall the statements made in the entire PDF are based on the GHG hypothesis being factual as presented by Hansen. IF you accept his hypothesis the paper is somewhat accurate but really does not talk about paleoclimate, only the CO2 to temperature relationships and is accurate in places that no assumptions were made. What it actually indicates is that CO2 follows temperature and is powerless to stop natural cooliing. By not looking at WHY CO2 follows temperature they make a grave error and that makes the recommendations misleading. Temperature increases allow increased biomass, both flora and fauna. In warmer climate the increased biomass creates the increased CO2 by simply breathing. The higher the faunal population the higher the CO2. There is indeed a feedback loop buit it is fauna feeds flora then flora feed fauna and loops to increase biomass. There are no major extinctions caused by increased CO2. This is quite clear in the fossil record so it is not harmful to the planet. The event 34 million years ago was a rapid cooling that appears to involve cometary impact. There is a new publication coming out that is described here: Earth Under Global Cooling ScienceDaily (Apr. 9, 2009) — "Thirty-four-million years ago, Earth changed profoundly. What happened, and how were Earth's animals, plants, oceans, and climate affected? Focusing on the end of the Eocene epoch and the Eocene-Oligocene transition, a critical but very brief interval in Earth's history, GSA's latest Special Paper provides new answers to these questions." ... "multiple extraterrestrial bolide impacts, possibly related to a comet shower that lasted more than two million years, may have played an important role in deteriorating the global climate." ... I am looking forward to this book. It may clear thing up a bit, but then it may just muddy the waters even more.
129845. Quietman at 03:18 AM on 27 April 2009
        It's the sun
        ps I downloaded chapter 6: "Palaeoclimate" and will go over it carefully. I'll let you know if I see any discrepancies (Paleontology is my thing).
129846. Quietman at 03:12 AM on 27 April 2009
        It's the sun
        Patrick Are you starting to see my issue with chris here? This is exactly what I tried to point out earlier. Those of us in non-theoretical sciences and professions follow the laws of thermodynamics to practical ends and know that they can not be violated. They simply can not be applied to open systems, ie. living things and the earth itself precisely because they are open systems. It's the reason that climate models do not work. ps I have been following you on various threads and this is really the only point that I can fully disagree with you on (other than your understanding of ENSO which I only disagree with you on root cause). Gord Overall I agree with you, especially about the IPCC but other as mentioned to Patrick above, he has some valid points. I want to thank both of you for a little more insight.
129847. Philippe Chantreau at 02:55 AM on 26 April 2009
        How to cherry pick your way to Antarctic land ice gain
        WA: So far, the Steig paper has been "refuted" only on "skeptic" blogs, not in the litterature. Since you doubt the guardian's labeling, why don't you try to find for us what the immense majority of scientists who study climate all the time really "believe"? And sorry, no, Heartland Institute lists do not count. "Contradictory papers on land ice?" How about some links? This source does not appear too ambigous. http://www.csr.utexas.edu/grace/ Accelerated loss at the margins is not incompatible with increased accumulation at the pole. If there is increased accumulation at the pole, it is hard to imagine how that could happen other than by increased moisture. That would happen to be what the models show. Your characterization of sea ice is, well, a characterization. It's best to look at the data: http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/global.daily.ice.area.withtrend.jpg Tells a different story. You have lots of assertions but no references.
129848. Lee Grable at 18:55 PM on 25 April 2009
        How to cherry pick your way to Antarctic land ice gain
        So, it isn't true that Antarctica is gaining ice? Well, concidering the last article posted on this site, ya'all were fooled to. I like this site.
        Response: Did you read the full post above? Where it says people "fail to distinguish between land ice and sea ice which are two separate phenomenon". Sea ice is increasing. Land ice is falling. The Australian article confuses the two to mislead people into thinking land ice is increasing.
129849. Lee Grable at 18:43 PM on 25 April 2009
        How to cherry pick your way to Antarctic land ice gain
        The skeptic arguement also has the distinct advantage of being the arguement that people want to believe. It's no coincidence that as the economy gets worse, more people don't believe in global warming( or just don't care as much). Just one less thing to worry about.
129850. David Horton at 09:16 AM on 25 April 2009
        Is the climate warming or cooling?
        Steve - you think "I continue to earnestly hope for some significant global warming" and what leads up to it (ie the continuing mythology of a "fall in global temperatures") should simply be left to sit there? Too much denialism, overt or subtle, goes unchecked, and next thing you have Plimer's magnum opus, providing ammunition for another ten years of delay in response by governments on the basis that the debate is continuing.
        Response: Note - I've deleted some of the comments as they add nothing to the scientific debate. But I've left this one up just to make a point. David, I certainly do believe we should work hard to expose the erroneous science in global warming skeptic arguments. But how we do that is important too. Attacking people rather than their scientific arguments is mental laziness. Taking a combative approach really achieves nothing except alienate people - both the person you're opposing and third party onlookers - who are the people you're more likely to persuade than a hard core skeptic. Sometimes it's difficult to take a polite, respectful tone - I find myself getting a little hot under the collar in some discussions - but try to discipline myself to control my emotions. I suggest you do the same, particularly on this site. Thanks!

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